As of the release of Mac OS X Mountain Lion, Apple no longer includes the Quartz X11 framework as a part of the OS install. Therefore, for develpoers that use this framework, Quartz X11 needs to be downloaded and installed seperately. Please follow the steps below to complete this installation.
1. When installing Fender® FUSE™, you will first be prompted to install the Mono Framework. Once you have completed installing that, you will be prompted that you need to install Quartz X11 as shown below. Click Continue.
2. Next you will be linked to this Apple support web page. On this page, click the 'http://xquartz.macosforge.org' link in the first paragraph.
3. After clicking the link on the Aplle support page, you will be taken to the X Quartz download page pictured here. Under download,
click "XQuartz-2.7.2.dmg" to download the installer for Quartz X11.
4. Once the download is complete, locate and double click on the Quartz X11 installer, and you should then see the XQuartz.pkg file
as shown here.
5. On this screen, click Continue.